Rotary engine.



l E. C. WARREN. A

ROTARY ENGINE.

l le 900. Ben ed Feb 90 (No Nodei.)

vPatmed Aug. I3, |001.

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CT Em (Application med .rm a1, woo. Renewed Feb. o, 1901.)

7 Sheets-Sheet 2.

(No Model.)

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Nn. 680,5|0.` Patented Aug. I3, I90I.

` E. C. WARREN.

ROTARY ENGINE.

(Application led Jan. 31, 1900. Renewed Feb. 5, 1901.)

(No Model.) 7 sheets-sheet 3.

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Patented Aug. I3, |901.

No. 680,5l0.

` E. c. WARREN. ROTARY ENGINE.

(Application led Jau. 31, 1900. Renewed Feb. 5, 1901.)

7 Sheets-Sheet 4.

(No Model.)

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no. 68mm.- Patented Aug. I3, |901.'

E. c. WARREN. l

` ROTARY ENGINE. (Application led Jan. 31, 1900. Renewed Feb. 5, 1901.)

(Ilo Model.)

Patented Allg. I3, I90I.

` E. C. WARREN. ROTARY ENGINE. YApplication led Jan. 31, 1900. R.e.ne\.ved Feb. 5, 1901.;

7 Sheets-Sheet 6.

Modell) No. 680,5I0. Patented Aug; I3, |90I. E. C. WARREN.

ROTARY ENGINE.

kApplication led Jan. 31, 1900. Renewed Feb. 5, 1901.) A (No Model.) 7'Sheets-Sheet 7-..

UNITED t STATES "PATENT FFIcE.

EDWARD o. WAR-REN, OF oniOAGO,-iLL1NOIs.

lROTARY ENGINE.

SPECIFICATION forming part of Letters Patent No. 680,510, dated August 13, 1901.

Application iiled January 31, 1900. Renewed February 5, 1901. Serial No. 46,154. (No model.)

To @ZZ whom, it may concern:

`13e it known that I, EDWARD C. VARREN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Rotary Engines, of which the following is a specification.

The objects of my invention are tovprovide a relatively simple, compact, and highly efficient rotary engine; to avoid the use of cams, eccentrics, crank-arms, and all similar devices which tend to limit the speed of a rotary engine and also to dispense With the use of packing; to balance the pressure on all rotating parts, so as to secure a minimum of friction and avoid unevenness of wear, and also to balance the pressure on the reversing- Y valves; to provide a system of ports, valves,

and Operating means for quickly and easily reversing the engine; to provide an improved arrangement of ports, pistons, and abutments, and to thereby avoid dead-centers; to provide a practical and efficient form of compound double-expansion engine; to provide an improved and novel arrangement whereby full boiler-pressure may be admitted directly tothe low-pressure cylinder, and to provide certain details of construction tending to increase the general efficiency of this type of engine.

To Tho attainment of the foregoing and other useful ends, my invention consists in mattersl hereinafter set forth and described.

In the accompanying drawings, Figure 1 is a perspective of a compound double-expansion rotary engine embodying my invention. Fig. 2 is a vertical, central, and longitudinal section of the same. Fig. 3 is a horizontal central section. Fig. 4 is a transverse section through the high-pressure cylinder on line :c in Fig. 3. Fig. 5 is a similar section through the intermediate-pressnre cylinder on line y y in Fig. 3. Fig. 6 is a transverse section through the low-pressure cylinder on line .sain Fig. 3. Fig. 7 is a longitudinal section throughY one of the two reversingvalve chambers mounted upon the high and low pressure cylinder casing, the said section p being taken on line x xin Fig. 4. Fig. 8 is a similar section ofthe other of the said valvechambers, taken on a line .fr c? in Fig. 4. Fig. 9 is a longitudinal section through one ofthe two reversing-valve chambers mounted upon 4the loW-pressure-cylinder casing, such section being taken on line y 1j in Fig. G. Fig. l10 is a similar section through the other of the said two reversing-valve chambers on line y2 y2 in Fig. 6. Fig. 1l is a view ot' one of the dat horseshoe-shaped rings which are arranged upon the abutment-shafts.

The engine which I have illustrated and described comprises three cylinders or pistonchambers and a like number of inclosed pistous. Steam is primarily admitted to the first or high-pressure chamber, exhausted from the high-pressure cylinder into the second or intermediate-pressure cylinder, and from the latter exhausted into the third or low-pressure cylinder. In the first or highpressure cylinder the piston is at all times subjected to full boiler-pressure, and for this reason the engine may be properly termed a compound double-expansion rotary engine.

In constructing an engine of the foregoing description I first provide a base or bed A, adapted to afford a suitable support for the two cylinder-casings B and C. Separate casings may be provided for the three cylinders or piston-chambers, if so desired; but as a matter of further improvement the casing B is adapted to afford high and intermediate pressure cylinders or piston-chambers, while the casing C is constructed to provide a lowpressure cylinder or piston-chamber. The casings may be cast and properly bored to receive the pistons and may be provided with suitable heads or end plates b b and c c. The casing B is, as previously stated, adapted to afford high and intermediate pressure pistoncham-bers, and to such end the inclosed piston D is provided with a peripheral flange d, which serves to divide the interior of the casing into two annular compartments or pistonchambers. (See Figs. 2 and 3.) The cylindric piston D is also preferably provided With a couple of end flanges d and cl2, and the i11- tervening spaces E and F between the latter and the flange d form, respectively, the high and intermediate pressure cylinders or pistonchambers. The rotary piston D is keyed to the shaft G, the latter being supported for rotation in suitable bearings a, ot', and a2 and the heads or end plates b b' being pro- IOO are supported, respectively, in bearings att" and a a6, and the heads or end plates b and b are preferably provided with stuffing-boxes b4 b5 and bs 67, through which the shafts H and I, respectively, extend.

Keyed to the shaft H, so as to rotate therewith, are a couple of cylindric abutments h and h', and similarly mounted upon the shaft I area couple of like abutments and fi. The

abutments h and t' are so arranged that their peripheries extend within the annular pistonchamber E vand make contact with that portion ofthe outer surface of the piston D which is included between the flanges d and d. In this way the said abutments h and t' are adapted to form a backing for the steam-pressure exerted in piston-chamber E, and in order to permit the piston projections d3, d4, d5, and d6 to pass the abutments the latter are provided, respectively, with recesses 1 land 2 2. The rotary abutments 7L and t are similarly arranged with reference to the annular piston-chamber F, and in order to permit the piston projections C17, d8, C19, and d10 to pass the said abutments the latter are provided with recesses 3 3 and 4 4.

Arranged loosely upon the shaft II are three flat horseshoe-shaped rings h2, h3, and h4, and mounted likewise upon the shaft I are three similar rings 2, i3, and t4. The middle ones of said rings serve to divide the abutmentchambers into two compartments and may be regarded practically as continuations of the piston-flange d, the rings being of the same thickness as the saidlange and arranged opposite the latter, as shown in Fig. 3. The other rings serve as end Walls for the abutment-chambers, are arranged opposite the flanges d and d2, and may be regarded as continuations of the latter, it being observed that the said flanges form the outside end Walls of the two piston-chambers and that each abutment fits and revolves snugly between a couple of piston-flanges and a couple of horseshoe-shaped rings. Each ring is provided with a marginal recess or notch, which conforms to the periphery of the piston-flange and which gives the ring the aforesaid horseshoe-shaped forinlor appearance. (See Fig. l1.) The rings may, if so desired, be formed integral with the casing-that is, the middle one integral With the casing B and the end ones integral with the heads b and b-but as a matter of improved and advantageous construction I prefer to adopt the arrangement shown and described, for with the rings madev integral with the casing some difficulty would be experienced in assembling the different parts of the engine, as in such case the abutments would have to be first placed in their respective positions and the abutment-shafts then slipped through and the abutments keyed, Whereas with the construction shown the rings and abutments may all first be properly mounted upon the shaft and the whole then placed in position Within the cas ing Without difficulty.

As a means for balancing the pressure of 4the steam upon the rings and abutments and as a means for keeping'the latter in contact with the pistons, or, in other Words, as a means for counteracting the pressure exerted upon the abutments bythe steam in the pistonchalnbers, the casing is preferably formed With` pressure spaces or cavities bs and b9. The said spaces or cavities are arranged back of the abutments, and the steam carried from the piston-chambers by the abutment-recesses serves to maintain in such cavities or spaces the desired degree of pressure. As the piston projections in the high-pressure piston-chamber preferably alternate with the piston projections in the intermediate-pressure piston-chamber, the recesses in the abutments allotted to the said two chambers are also preferably arranged to alternate. The piston projections operating, respectively, Within the high and intermediate pressure chambers are preferably four in number in each case, while the recesses with which each rotary abutment is provided are preferably two in number. fore, of the rotary piston D it is obvious that the rotary abutments must revolve twice, and to this end the gears U, V, and W, by which the shafts G, I-I, and I are connected, are so proportioned relatively as to obtain a speed of rotation on the part of the shafts II and I exactly double that which may be 'imparted to the shaft G. By such arrangement there Will be little or no friction between the piston and abutments, as the latter have simply a rolling contact with the former, and while the number of piston projections and coperating abutment-recesses may be varied, as desired, I prefer the arrangement and number described and-illustrated.

Steam is admitted primarily to the high-pressure cylinder or piston-chamber by way of an inlet-pipe .Lexhausted from 'the high-pressure chamber into the i Intermediate-pressure chamber and from the latter then exhausted into the low-pressure cylinder by way of a pipe K. For the purpose of reversing the engine I have provided suitable piston-valves, which are arranged for reciprocation within suitable valve-chambers formed in the casings B and C. The two piston-valvesL and M, which control the admission and exhaust ports leading to and from the high and intermedi-ate pressure chambers, are arranged for reciprocation, respectively, within the valve-chambers bw b, which latter are preferably bored IOO For every rotation, there- IOS IIC

or suitably formed within the cylinder-casing B. The piston-valve L, as illustrated, comprises a piston rod or stem Z and three disks or piston-heads Z,'Z2, and Z3, mounted upon the rod or stem and tted to slide within the valve-chamber-bw. The valve M is similar in form and construct-ion to the valve L and consists of a piston-rod m and three disks or heads m', m2, and m3. Each valve-chamber may be provided with heads adapted to be screwed into the casing, and the pistonrods may be arranged to extend and work through stuffing-boxes of any suitable construction. (See Figs. 7 and 8.)

Referring now to Figs. 4, 5, 7, and S, steam will pass from the inlet-pipe J into a duct or passage 5, which latter extends transversely across and through the upper portion of the casing B. The ends of the said duct or passage 5 communicate with the Valve-chambers Z210 and bu. With the valves in the position shown in Figs. 7 and 8 steam will pass from the duct 5 into the space between the disks Z2 and Z3 in the chamber Z910 and also into the space between disks m2 and m3 in the chamber bu. From Valve-chamber bw steam will enter the annular piston-chamber E by way of port 6 and by exerting pressure upon the piston projection Z3 drive the piston D in the direction indicated by the arrow. At the same time, however, steam will pass from the valve-chamberb11 by way ot' port 7 and entering the piston-chamber E contribute to the rotary movement of the piston by exerting pressure upon the piston projection d5. By thus permitting steam to enter the pistonchamber at opposite points the pressure upon the outer surface of the piston will be balanced, thereby preventing unevenness of wear and reducing the friction of the shafts or journals revolving in their bearings to a minimum. Vith the piston rotating in this direction the exhaust from the chamber E will take place through ducts S and 9.

Referring to Figs. 4, 5, 7, and 8, it will be seen that exhaust-steam is entering the port or duct 8 from between the piston projections CZ4 (Z5, and also that exhaust-steam is entering port or duet 9 from between piston projections CZ3 d3. The steam which enters duct 8 will pass into the space between disks Z Z2 in Valve-chamber Z710, While at the same time steam from duct 9 will enter space between disks mm2in valve-chamber bi1. From the space between the two disks Z Z2 in valvechamber Z910 the exhaust-steam from the highpressure chamber will pass into piston-chamber F by way of d uct 10, while from the space between the two disks m m2 in Valve-chamber b exhaust-steam will enter piston-chamber F by way of the port or duct 11. The piston-chamber F is, it will be observed, substantially three times the size of chamber E, and the piston projections in the former present, therefore, substantially three times the pressure-surface presented by the piston projections in the latter. Such being the case,

steam passing from between the piston projections Z4 Z5 in the high-pressure chamber will be free to expand between piston projection di and abutment h in the intermediatepressure cha mber,and at the same tim esteam from between piston projections d3 CZ6 will be permitted to enter and expand between piston projection d10 and abutment i. The steam carried around between piston projections CZ9 and d10 will exhaust into the port or duet 12, while steam carried between piston projections CZ7 Z3 will exhaust into duct 13. Extending across and through the upper portion of the casing B is a duct or passage 14, which communicates at each end with the valve-chambers Z910 and Z211. Steam entering the space between disk Z. and the end wall of valve-chamber i210 will escape therefrom by way of said duct 111 and from the latter will then enter the pipe K, which leads to the lowpressure cylinder. In a similar manner, entering the space between disk fm and the end Wall ot' valve-chamber b11,it will pass into duct 14, and from the latter will also be conveyed by way of pipe K to thelow-pressure cylinder. The longitudinal ducts or passages 15 and 16, which extend, respectively, above the two valve-chambers Z210 and b, serve not only to balance the reversing-valves, but also as mediums of communication between the high and intermediate pressure chambers when the reversing-valves are shifted for the purpose of reversing the engine. Assuming that the said valves have been shifted to the opposite ends of their respective chambers, it will be seen that steam will then pass from the duct 5 into and between the disks Z2 Z3 and from such space into the piston-chamber E by way of duct 8. Also in such case steam will en'- ter the space between the disks m2 m3 in chamber bu and from the latter pass into the piston-chamber E by way of duct 9. The rotary piston by such admission of steam will be rotated in the opposite direction, and the exhaust from the high-pressure chamber will then take place throughducts 6 and 7. Exhaust-steam admitted to duct 6 will pass into the space between disk Z3and the end wall of valve-chamber Z910, while in a similar manner steam will enter the space between disk m3 and the end wall of valve-chamber ou. From the said space between the disk Z3 and the end wall of chamber blo steam will then pass into duct 15 and be admitted to chamber F by way of duct 12, it. being understood at this juncture that sufiicient space exists between the disk Z and the end wall of the valve-chamber to insure and establish com- IOO IIO

munication between the ducts 15 and 12. Y

Steam admitted to the space between the disk m3 and the end wall of chamber Z211 will enter the intermediate-pressure chamber by way of ducts 16 and 13, and the exhaust therefrom will then take place through ducts 10 and 11. Such exhaust passing from duct lO into and between the disks Z' Z2 will escape into pipe K by way of duct 14, and the exhaust received between the-disks m m2 by way of duct 11 Will escape in a like manner by way of duct 14. Referring now to Figs. 2, 3, G, 9, and 10, the low-pressure portion of the engine comprises a casing, piston, and abutments somewhat similar in form and construction to the high and intermediate pressure portion, but relatively large and involving practically but one piston-chamber. The casing C, which is adapted to afford a suitable piston-charnber for the piston N, may be provided, as previously stated, with heads c c and also with stuffing-boxes c2 c3, through which eX- tends the shaft G. The said piston N is cylindric in form and provided with peripheral iianges n, n', and n2. The latter are arranged so as to divide the interior of the casing into annular compartments, and the piston proj ections of one compartment or chamber preferably coincide with those of the other compartment. Arranged at each side of the piston N and preferably in the same plane as the shaft G are a couple of shafts Q and P. The said shafts are supported for rotation in bearings al' a and a am, respectively, and each shaft is arranged to extend through suitable stufting-boxes c4 c5 and c6 c7. Keyed to shaft O are a couple of cylindric abutments o and o', and similarly mounted upon the shaft P are a couple of similar abutments p and p. The said abutments extend Within the piston-chambers, so as to make contact with the piston N, and are similar yin function and operation to the abutments previously described. The abutments o and p are provided, respectively, with notchesl or recesses 17 1.7 and 18 18, so as to permit the piston projections n3, n4, 77.5, and n to pass, and the abutments o and p are provided, respectively, with similar notches 19 19 and 2O 20, with reference to the continuation of such piston projections on the other side of the `flange a'. The said abutments, like those of the high and intermediate pressure chambers, are preferably arranged to make two revolutions to one on the part of the rotary piston, and to this end the gears X, Y, and Z, which connect the shafts O, P, and G, are so proportioned relatively that for each revolution given the latter two revolutions will thereby,be given the former. In this Way a rolling contact is secured between the abutments and piston and friction reduced to a minimum. A couple of steam-spaces c8 o9 are -also formed within the casing C, the steam-space G8 being located back of the abutments o and o and the steam-space a9 being located at the opposite side of the engine and back of the abutments p and p'. The steam carried from the piston-chambers by the recesses in the several abutments serves to maintain a constant pressure in the said steam-spaces and in such way to keep the abutmen ts in contact with the piston. Three flat horseshoe-shapedrings o2, o3, and o4 are loosely mounted upon the shaft O, and three similar rings are arranged upon the shaft P.

The said rings are similar in form and function to the rings previously described in connection with the high andinterniediate pressure portions of the engine and for this reason do not require further description.

Exhaust-steam from the intermediate-pressure chamber is primarily admitted to the low-pressure 4chamber by way of pipe R and is ultimately exhausted from such chamber by way of an outlet-pipe Q. The ports or ducts by which steam is admitted to and exhausted from the low-pressure piston-chamber are preferably controlled by a couple of reversing valves R and S, similar to the valves L and M. The said valves are arranged for reciprocation, respectively, within valvechambers c10 and (informed within the casing C, and each valve preferably comprises a piston rod or stem anda couple of heads or disks mounted thereon. For exam ple, the valve R may consist of a piston-rod r, provided with a couple of heads or disks r' r2, andthe valve S may consist of apiston-rod s, provided with a couple of disks s and s2. Extending transversely across and through the upper portion of the casing C is aduct or passage 2l, which communicates at each end with the two valve-chambers 01 and c and whichA communicates at its middle portion with the pipe K. Steam entering the duct or passage 21 from the said pipe will be conducted by said duct to the two valve-chambers, and with the valves in the position shown in Figs. 9 and l() will enter such chamber at points between the disks or heads of each valvethat is to say, steam entering the valvechamber 010 will be received between the disks 1" and r2, while the steam entering the valvechamber c will be received between the disks s' and-s2. From the space between the two disks r' and r2 steam Will-pass by way of port 22 into both compartments of the lowpressure chamber, and at the same time therewith steam from the space between the disks s and s2 will pass by way of port 23 and also enter both compartments of the lowpressure piston-chamber. Steam entering the two compartments of the low-pressure chamber by way of port 22 Will expand betweenthe piston projections and the abut-- ments p p', while the steam entering by way of the duct 23 will expand between the piston projections and the abutments o o. By such expansion on the part of the steam the piston will be rotated in the direction indicated by the arrow, and as the pistons D and N are both keyed to the shaft G the two pistons will therefore rotate in unison and maintain their relative positions. With steam entering and driving the pistons in the direction indicated the exhaust from the lowpressure chamber will take place through ports 24 and 25. Exhaust-steam entering the port 24E will be conducted to one end of the valve-chamber c, while the exhaust escaping by way of port 25 will be received by one end portion of the valve-chamber C10. (See IOO IIO

IZO

Figs.` 9 and IO.) above the valves and through the casing are a couple of ducts or passages 26 and 27, cony connect the opposite ends of the valve-chamber cu. Exhaust entering the valve-chamber om by way of duct 25 will pass into duct 26 and escape therefrom by Way of duct 28 and pipe Q, while exhaust entering the valvechamber c11 by way of duct 24 will pass into duct 27, and from the latter also escape by way ot' duct 2S' and pipe Q.

The ducts 26 and 27, while serving principally as a means of exhaust, also serve to balance'the two reversing-valves by permitting exhaust-steam to pass to the opposite ends of the valve-chambers, so as to exert a like pressure upon each end of the inclosed valve. The steam pressure between the disks of each valve is of course balanced at all times, and by thus balancing the pressure of the exhaust' the reversing-valves are easily and readily shifted when a reversal of the engine is desired. A reverse order of admission and exhaust to and from the low-pressure cylinder and a consequent rotation of the pistons in a reverse direction from that indicated is obtained by shifting or reciprocating the valves R and S to the opposite ends of their respective valve-chambers. By thus shifting the said reversing-valves to the opposite ends of their respective valve-chambers steam will then be admitted to the lowpressure chamber by way of ducts 24 and 25 and exhausted therefrom by way of ducts 22 and 23, for it will be observed that by such shifting of the valves the space between disks s' and s2 will then serve `to connect duct 24 with one end of duct 2l, so as to admit steam to the low-pressure chamber by Way of the former, and also that the space between disks i" and r2 will, in a similar manner and for a like purpose, serve to connect duct 25 with the other end of duct 2l. In such case steam entering the space between the disks of valve S by way of duct 21 will pass from said space into duct 24, and from the latter will then enter the low-pressure chamber at a point immediately below the abutments o and o', and steam entering the space between the disks of valve R, also by way of the said duct2l, will pass into duct 25 and from the latter will then enter the low-pressure chamber at a point immediately above the abutments p and p'. \Vith steam thus entering the lowpressure chamber the ports or ducts 22 and 23 will, as previously stated, then serve as exhaust ports or passages, as steam entering the low-pressure chamber by way of port or duct will exhaust by way of port or duct 22, while steam entering by way of port or duct 25 will exhaust by way of port or duct 23, for with the valves so shifted the space be- Extending longitudinally tween the disk r2 and the end Wa-ll of valvechamber 010 will serve to connect duct 22 with duct 26, while the space between disk s2 and the end wall of the valve-chamber c11 will serve to connect duct 23 with duct 27, and from said ducts 26 and 27 the exhauststeam will then finally escape by wayof duct 28 and pipe Q.

The reversing-valves may be operated in any suitable manner; but as a matter of further improvement I prefer to connect all ofthe valves for simultaneous shift or adjustment, so as to simultaneously reverse the order of admission and exhaust in all of the piston-chambers. As a simple and effective arrangement for so doing I provide a rockshaft T, mounted in suitable bearings t t. The said shaft is preferably arranged between the casings B and C, so as to extend transverselyT above the shaft G, and the bearings ttmay be conveniently mounted upon the bearings a7 and a". (See Figs. 1, 2, and 3.) The upwardly-extending crank-arms t t2 and 3 t4, with which the rock-shaft is provided, are adapted for connection with the four reversing-valves, and the hand-lever t5, secured to one end of the said shaft, isdesigned to afford a means for rocking or oscillating the latter for the purpose of shifting the said valves. The crank-arms t and t2 are connected by means of links t with the ends of the pistonrods s and r, respectively, and the crankarms t3 and t4 are similarly and respectively connected with the ends of piston-rods Zand m. With such provision and arrangement the four reversing-valves may be simultaneously shifted, so as to simultaneously reverse the order of admission and exhaust inv the three piston-chambers, it being observed that the valves are simultaneously shifted in the same direction. A rotary engine thus constructed is easily and quickly reversed, there being practicallyno steam-pressure to overcome in shifting the valves and the extent of throw necessary on the part of the hand-lever being comparatively small.

As a matter offurtheraud special improvement and with a view to affording means for increasing the power of the engine in case of a heavy load, provision is made for the admission of live steam directly to the lowpressure piston-chamber, whereby the latter may at any time be made to serve as a highpressure chamber. As a simple and edective arrangement forso operating the engine when desired, I provide a by-pass 29, whichserves to connect the primary inlet-pipe .I with the pipe K. The by-pass is preferably controlled by a suitable valve 30, and by operating the latter live steam may be admitted from the pipe J directly to the low-pressure chamber, in which case the latter will then serve as a high-pressure cylinder.

What I claim as my invention is- 1. A compound rotary engine comprising a casing and cylindric piston which rotates concentrically with said casing and which is pro- IIO vided with a plurality of annular flanges which divide the interior of the casin'ginto a plurality of annular compartments or pistonchambers, each compartment being provided with a plurality of piston projections which alternate with those of the adjacent or next compartment and rotary abutments arranged at opposite sides of the piston, and which are of a diameter to extend and rotate between the anges of the latter, and which are provided With a plurality of peripheral notches or cavities adapted to receive the projections on the piston during the rotation ofthe latter; the said casing being provided with suitable ports or passages for admitting and exhausting steam from one compartment to another, the said passages or ports being arranged so as to admit the steam at opposite or substantially opposite points for the purpose of balancing the pressure upon the piston, andA such casing being also provided withsuitable steam spaces or cavities for maintaining pressure upon the said rotary abut-ments, substantially as and for the purpose described.

2. A compound rotary engine comprisinga suitable cylinder or casing, an annular cylindric or drum-like piston which rotates concentric-ally within said casing and which is peripherally flanged intermediate of its ends in such manner as to divide the interior ofv the casing into a plurality otl annular compart ments, each compartment'being provided' with'a plurality of projections and the projections of one compartmentalternating with those of the adjacent or next compartment; one or more rotary abutments provided with peripheral notches adapted to receive the said projections on the rotary piston and arranged to cooperate with said piston; and suitable ports or passages whereby the steam may be admitted and exhausted from one compartment of the piston-chamber to another.

3. A compound rotary engine, comprising a suitable cylinder or casing, a cylindric piston which rotates concentrically within said casing and which is provided with a peripheral' flange at a pointintermediate of its ends, the said fiange serving to divide the interior of the casing into two compartments, a rotary abutment for each compartment, a horseshoe-shaped ring arranged between said abutments and opposite to or in line with said flange, and suitable ports or passages for admitting and exhausting the steam from one compartment to another.

'-t. A'compound multiple-expansion rotary engine, comprising high, intermediate and low pressure piston-chambers, the said chambers having suitable supply and exhaust ports; concentric rotary pistons mounted to rot-ate in unison upon a shaft and inclosed and operating within said piston-chambers,

the piston D being provided With end flanges d d2 and also with a flange d which is arranged adjacent tothe flange d, for the purpose stated; rotary abutments coperating with said pistons; the steam being primarily ad m itted to the high-presen re chamber wherein it operates to revolve the inclosed piston Without expanding; the exhaust from the said high-pressure chamber being received and expanded Within the intermediate-pressure chamber, and the exhaustfrom the latter being received and expanded Within the low-'pressure chamber.

5. A compound multiple-expansion rotary engine comprising high, intermediate and loT pressure piston-chambers; said chambers having suitable supply and exhaust ports; rotary pistons D and N mounted to rotate in unison upon a single shaft G and inclosed and operating within said piston-chambers and provided respectively with flanges d d' d2 and n 'n' n.2 for the purpose descri-bed; suitable abutments coperating with said pistons; thev steam being primarily admitted to the high-pressure chamber E and allowed to pass through the latter without expanding; the exhaust from the saidhigh-pressu re chamber being received by and expanded within the intermediate-pressure chamber F and the exhaust from the latter being received by and expanded Within the low-pressure chamber.

6. A compound rotary engine comprising high, intermediate and low pressure pistonchambers; pistons D and N rotating in unison upon a single shaft Within said chambers and provided respectively with flanges d, d', cl2 and n, n', n2, substantially as and for the purpose setv forth; and suitable inlet and outlet ports for admitting and exhausting steam to and from the said chambers; and suitable abutments cooperating with said pistons; the

steam being primarily admitted tothe highpressure chamber and exhausted therefrom to the intermediate -pressure chamber or chambers, and the exhaust from the latter being conveyed to the low-pressure chamber; and the said low-pressure chamber being provided with one or more live-steam openings, whereby the pressure in such chamber may be augmented by a direct admission of steam at full boiler-pressure, and whereby said chamber may be made to serveas a high-pressure chamber'.

7. A compound rotary engine comprising in combinationA the casing B providing a piston-chamber; a piston D rotating concentrically Within said chamber and provided with one or more piston projections and also with flanges d, d', d2 for the purpose set forth; a cylindric rotary abutment provided with one or more recesses adapted to receive the said piston projection or projections during the rotation of the piston; and suitable inlet and outlet ports for admitting and exhausting steam to and from the said pistonchamher.

8. A compound double-expansion rotary engine, comprising high, intermediate and low pressure piston-chambers; rotary pistons inclosed Within the said chambers and rotating in unison upon a single shaft; suitable abutments coperating with said pistons;

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suitable inlet and outlet ports for admitting and exhausting the steam to and from the said chambers; an inlet-pipe leading to the high-pressure chamber; an exhaust-pipe leading from the intermediate-pressure chamber to the low-pressure chamber; and a valvecontrolled `by-pass 29 leading from the said inlet-pipe to the said exhaust-pipe, whereby the said low-pressure chamber may be made to serve as a high-pressure chamber; the steam being primarily admitted to the highpressure chamber wherein it operates to rotate the inclosed piston Without expanding, the exhaust from the high-pressure chamber being received and expanded within the intermediate-pressure chamber,and the exhaust from the latter1 being received and expanded within the low-pressure chamber.

9. A rotary engine comprising in combination the casing C providinga piston-chamber; the piston N provided With flanges a n n2 and rotating concentrically within said chamber and provided with eight piston projections; acouple of cylndric rotary abutments located at opposite sides of the said piston, each abutment being provided with a couple of recesses adapted to receive the said piston projections during the rotation of the piston; the said abutments having a rollingor frictionless contact with the said piston; and the said casing being provided With suitable inlet and outlet ports for admitting and exhausting the steam to and from the said piston-chamber.

l0. A reversible rotary engine comprising in combination the casing C adapted to provide a piston-chamber; a pistonN provided with flanges 'n n' faz and rotating concentrically within said chamber and provided with one or more piston projeetions,such as shown; one or more rotary abutments provided with recesses adapted to receive the said piston projection or projections; the abutment shaft or shafts being gear-connected with the piston-shaft; and one or more piston-valves for controlling the supply and exhaust ports, whereby the engine may be reversed at Will.

11. A compound double-expansion reversible rotary engine, comprising in combination high, intermediate and loW pressure piston- ,chambers; the rotary flanged pistons D and N inclosed Within said chambers and constructed substantiallyas shown and described; suitable abutments coperati ng with-said pistons; suitable supply and exhaust ports for the piston-chambers, the steam being primarily admitted to the high-pressure chamberE wherein it operates to rotate the inclosed piston Without expanding; the exhaust from said high-pressure chamber being received and expanded Within the intermediate-pressure chamber F, which is larger than said high-pressu re chamber, and the exhaust from the chamber F being received and expanded Within the low-pressure chamber; suitable valves for controlling the said supply and exhaust ports; and means for operating said valves for the purpose of reversing the engine.

12. A compound reversible rotary engine, comprising the two cylinder-casings and pistons rotating therein; rotary abutments arranged at either side of each piston; a valvechamber adjacent to each abutment-chamber; a reciprocating piston valve in each valve-chamber; the casing having suitable ports or ducts which serve to connect the valve-chamber with the piston-chamber at opposite points so as to balance the pressure upon the pistons; a rock-shaft provided with crank-arms having suitable connection with the rods or stems of the four piston-valves, and a hand-lever for rocking the said shaft.

13. In a reversible rotary engine, the casing inclosing a rotary piston; the rotaryabutments cooperating with said piston; the casing having suitable ports 'for admitting and exhausting steam to and from the pistonchamber; a couple of reciprocating pistonvalves for controlling said ports; arock-shaft provided With crank-arms, links forconnecting the said arms With the stems or rods of the said valves, and a handelever for rocking said shaft.

14. A reversible rotary engine comprising a casing providing a piston-chamber; a piston rotating therein;.one or more abutments coperating With said piston; the casing having suitable ports for admitting and exhausting steam to and from the said piston-chamber, the steam being admitted at opposite sides of the piston so as to balance the pressure upon the latter; a couple of reciprocating piston-valves for controlling the said ports; a rock-shaft having suitable connection with the stems or rods of said valves; and means for rocking said shaft for the purpose of shifting the valves and thereby reversing the engine.

15. A compound double-expansion rotary engine, comprising a couple of rotary pistons mounted to rotate in unison upon a rotary shaft, a couple of cylinder-casings inclosing the said pistons, one of said pistons being flanged so as to divide the interior of the easing into high and intermediate pressure piston-chambers, and the other of the said two cylinder-casings being adapted to provide a low-pressure piston-chamber; rotary abutments arranged at each side of the said pistons and provided with recesses adapted to receive the piston projections, suitable inlet and exhaust ports for admitting and exhausting the steam to and from the piston-chambers, the steam being admitted Vto each piston-chamber at opposite points so as to balance the pressure upon the rotary pistons, and the steam being primarily admitted to the high-pressure chamber wherein it operates to rotate the inclosed piston Without expanding; the exhaust from the said high-pressule chamber being received and expanded within the intermediate-pressure chamber, and the exhaust from the latter being received and nally expanded Wi thin the 10W-pressure chamber.

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1G. A compound double-expansion rotary engine, comprising a couple of cylindric or drum-like rotary pistons keyed to a rotary shaft and arranged to rotate within a couple of cylinder-casings, one of said pistons being iianged so as to divide the interior of the casing in to high and intermediate pressure piston-chambers; rotary abutments cooperating with said pistons and arranged in the same plane as the piston-shaft, said abutments being recessed so as to permit the piston projections to pass, suitable supply and exhaust ports for admitting and exhausting the steam to and from the piston-chambers, the steam being admitted to each piston-chamber at opposite points so as to balance the pressure upon the inclosed pistons, and the steam being primarily admitted to the high-pressure compartment wherein it operates to rotate the inclosed piston without expanding; the eX- haust fromi the said high-pressure chamber being received and expanded within the intermediate-pressure chamber-,and the exhaust from the latter being received and finally expanded within the low-pressure chamber; and the said piston-shaft being gear-connected with the said rotary abutments whereby the latter will have a rolling contact with the former.

. l' 7. A compound doubleexpansion rotary engine, comprising a couple of cylindric or drum-like rotary pistons mounted to rotate in unison upon a horizontal rotary shaft, a casing inclosing each piston, one of said pistons being flanged so as to divide the interior of one casing into high and intermediate pressure piston-chambers, rotary abutments arranged at each side of the said pistons and in the same plane as the piston-shaft, horseshoeshaped rings arranged upon the abutmentshafts opposite to the piston-flanges, steamspaces back of the abutments and rings for the purpose of keeping the said abutments in contact with the pistons, the said abutments being provided with notches or recesses adapted to receive the piston projections during the rotation of the pistons, and the said abutments being gear-connected with the piston-shaft whereby the former will have a rolling contact with the said piston; suitable supply and exhaust ports for admitting and eX- hausting steam to and from the piston-chambers, the steam being admitted at opposite points so as to balance the pressure upon the pistons, and the steam being primarily adi mitted to thehigh-pressure chamber wherein it operates to rotate the inclosed piston without expanding; the exhaust from the said high-pressure chamber being received and expanded Within the intermediate-pressure chamber, and the exhaust from the latter being received and expanded within the lowpressure chamber.

18. In a rotary engine, a casing adapted. to provide a piston-chamber,a cylindric or drumlike piston rotating within said chamber and provided with one or more piston projections, and the said piston being also provided with a ange which serves to divide the pistonchamber into two compartments; one or more rotary abutments provided with one or more recesses or notches adapted to receive the said piston projection or projections, the said abutment or abutments having a rolling contact with the said piston, and one or j more horseshoeshaped rings looselyT mounted upon the abutment shaft or shafts and arranged opposite the said piston-harige; and the said casing being provided with suitable inlet and outlet ports for admitting and exhausting the steam to and from the piston-chamber, and

said casing being also provided with one or more pressure spaces or cavities for balancing the pressure upon the said abutment or abutments and keeping the latter in contact with the said piston.

19. In a rotary engine, a casing adapted to provide a piston-chamber,a cylindric or drumlike piston rotating concentrically within said chamber and provided with four oppositelyarranged piston projections, the said piston being also providedA with three peripheral iian ges which serve to divide the piston-chamber into two compartments; a couple of rotary shafts arranged at opposite sides of the piston and gear-connected with the pistonshaft, two rotary abutments keyed to each of said rotary shafts, the two abutments on one shaft being arranged to project respectively within one and the other of the said two'compartments at one side of the piston, and the two abutments on the other shaft being arranged in a similar manner on the opposite side of the said piston; each abutment being provided with a couple of recesses adapted to receive the said piston projections, and the said abutments having a rollingcontact with the piston; three horseshoe shaped rings loosely mounted upon each abutment-shaft, the said rings being arranged opposite the piston-flanges, and the cylinder-casing being provided with pressure chambers or cavities whereby the said abutments are kept in contact with the rotary piston.

20. In a compound rotary engine, a cylin-` der-casing and a piston rotating concentrically therein, the said piston being iianged so as to divide the interior of the casing into two compartments, and the said piston being also provided with piston projections whereof those of one compartment alternate with those of the other compartment; two or more rotaryabutments provided with recesses adapted to receive the said piston projections during the rotation of the piston, one or more horseshoe-shaped rings arranged upon the abutment shaft or shafts opposite the piston iiange or flanges, and one or more pressure spaces or cavities for keeping the said abutments in contact with the piston; one or more inlet-ports for admitting steam to one of saidv two compartments, ports or ducts for convey- IOO IIO

ing the exhaust from such compartment to the other compartment, and suitable ports or ducts for exhausting from the latter.

21. In a compound rotary engine, a cylinder-casing and a piston rotating concentrically therein; the said piston being ianged so as to divide the interior of the casing into two compartments, and the piston being also provided with piston projections, preferably four in each compartment, and those of one compartment alternating with those of the other compartment; a couple of rotary shafts arranged at opposite sides of the piston and gear-connected with the piston-shaft, two cylindric abut-ments keyed to each rotary shaft in such manner as to provide each compartment with two oppositely-arranged rotary abutments, and horseshoe shaped rings loosely mounted upon the abutment-shafts' and arranged opposite the piston flange or flanges, the cylinder-casing being provided with pressure spaces or cavities for keeping the abutments in contact with the piston; and the said casing being also provided with ducts or ports whereby the steam will be primarily admitted to one of said compartments wherein it will operate to rotate the inclosed piston without expanding, and whereby the exhaust from such compartment will be received and expanded Within the other of the said two compartments.

22. In a reversible rotary engine, a casing adapted to provide a piston-chamber, a cylindric or drum-like piston rotating concentrically within the said chamber and provided with a plurality of piston projections, a couple of abutments arranged at either side of the said piston and provided with recesses adapted to receive the said piston projections, the said ab utments being gear-connected with the piston-shaft, and the said casing being provided with suitable inlet and outlet ports for admitting and exhausting steam to and from` the piston-chamber, the steam being admitted at opposite points so as to balance the pressure upon the piston; a couple of pistonvalves arranged for reciprocation in suitable valve-chambers and adapted to control the admission and exhaust ports, and means for operating said valves whereby the engine may be reversed at will.

23. In a reversible rotary engine, a casing adapted to provide a piston-chamber, a cylindric piston rotating concentrically in said chamber and provided with piston projections, rotary abutments arranged at either side of the piston and provided with recesses adapted to receive the piston projections, a couple of valve-chambers formed within the cylinder-casing, each valve-chamber having one or more ports leading to and communicating with the piston-chamber at a point immediately above the adjacent abutment, and each valve-chamber having one or more ports leading to and communicating with the piston-chamber ata point immediately below the said abutment; the opposite ends of each valve-chamber being connected by means of one or more ports or ducts, and each valvechamber being provided with supply and exhaust ports or ducts; a piston-valve in each valve-chamber adapted to control the said ports or ducts, and means for shifting or reciprocating said valves for the purpose ot' reversing the engine.

24. In a reversible rotary engine, a casing adapted to provide a piston-chamber, a cylindric piston rotating concentrically therein and provided with piston projections, rotary abutments arranged at either side of the piston and provided with recesses adapted to receive the piston projections, a valve-chamber formed in the casing above each abutment, a duct or passage above each valvechamber serving to connect the opposite ends of such chamber, an exhaust duct or passage connecting the said valve-chambers, a supply duct or passage also connecting the two valvechambers, an inlet for the said supply-duct and an outlet for the said exhaust-duct, one or more ports or ducts leading from each valve-chamber to and communicating with the piston-chamber at a point immediately above the adjacent abutment, and one or more ducts or ports leading from each valvechamber to an'd communicating with the piston-chamber at a point immediately below the adjacent abutment; a pistonvalve in each Valve-chamber, and means for shifting the said valves for the purpose of reversing the engine.

25. In a compound reversible rotary engine, a cylinder-casing and a piston rotating concentrically therein; the said piston being flanged so asto divide the interior of the casing into two compartments, and being also provided with a plurality of piston projections whereof those of one compartment alternate with those of the other compartment; a couple of rotary abutments arranged at opposite sides of the piston and having recesses adapted to receive the piston projections; suitable ports for admitting and exhausting steam to and from one of said compartments, suitable ports for conveying such exhaust to the other compartment, exhaust-ports for the latter, a couple of piston-valves for the purpose of reversing the engine.

26. In a compound reversible rotary engine, a cylinder-casing and a piston rotating concentrically therein; the said piston being lianged so as to divide the interior of the casing into two compartments, and being also provided with a plurality of piston projections whereof those of one compartment alternate with those of the other compartment; rotary abutments arranged at either side of said piston and having recesses adapted to receive the piston projections, a valve-chamber adjacent to each abutment, and a duct or passage connecting the opposite ends of each valve-chamber; each valve-chamber havinga couple of ports leading to and opening into the two compartments at points immediately IOO IIO

above the adjacent abutment, and each valvechamber having a couple of ports or ducts leading to and openinginto the said two compartmen ts at points immediately below the adjacent abutment; an admission-port for each valve-chamber, and an exhaust-port for each valve-chamber; a piston-valve inclosed within each valve-chamber, each valve consisting of a piston-rod with a plurality of disks or heads, and means for shifting the valves for the purpose of reversing the engine; the steam being primarily admitted to one compartment wherein it operates to rotate the inclosed piston Without expanding, and the exhaust from such compartment being received and expanded within the other` of the said two compartments.

27.1A compound double-expansion rotary engine, comprising high, intermediate and lovvl pressure piston-chambers', pistons rotating-concentrically Within said chambers, r0- tary' abntments cooperating with said pistons, a plurality of valve-chambers having-ports or ductsleading to and communicating withA the piston chambers, piston-valves in said valve-chambers adapted to control the admission and exhaust of steam tov and fromv the piston-chambers', ports or ducts yfor primarily admitting steam to such valve-chambers, and ports or ducts for permitting the exhaust to escape from said valve-chambers; the steam being primarily admitted t0 the high-pressure chamber whereinit operates'torotate the inclosed piston Without expanding, the exhaust from said high-pressu re chamber being received and expanded within the intermediate-pressure chamber, and the exhaust from the latter being received-and expanded within the low-pressure chamberg'and means for simultaneously shifting the said valves for the purpose of reversing the order of admission and exhaust to and from the pistoncham ber,whereby the engine may be reversed at will. f

28. A compound double-expansion reversible rotary engine, comprising high, intermediate and low pressure piston-chambers, pistons rotating concentric-ally within said chamb-ers, rotary abutments cooperating with said pistonsga couple of valve-cham bers adjacent to the high and intermediate pressure chambers and having suitable ports orducts leading to the said piston-chambers, and a threedisked piston-valve in each valve-chamber; a couple of valve-chambers adjacentA to the low-pressure chamber and having suitable ports or ducts leading to the latter, and a Iwo-disked piston-valve in each of saidvalvechambers; the steam being first admitted to the valve-chambers adjacent to the high and intermediate pressure chambers, andl from the latter admitted to the high-pressure chamber wherein it operates to rotate the inclosed piston without expanding; the exhaust from the high-pressure chamber being allowed to escape back into the said adjacent valvechambers, and from the latter permitted to pass into and. expand withinthe intermediate-pressure chamber; the exhaust from the low-pressure chamber being also conducted back to the adjacent valve-chambers, and from the latter allowed to escape intoV the valve-chambers adjacent tothe low-pressure chamber; the steam thus entering the valvechambers adjacent to the low-pressure chamber being then received and expanded within the said'loW-pressure chamber, the exhaust vfrom the latter being then conducted back to ysuch adjacent valve-chambers, and from the latter permitted to escape from the engine; and means for simultaneously shifting the said reversing-valves for the purpose of reversing the engine.

29. In a reversible rotary engine, a casing adapted to provide a piston-chamber, a piston rotating therein, a couple of oppositely-arranged abutments coperating with said piston, the casing being provided with ports or ducts for admitting and exhausting steam to and from the said piston-chamber, the steam being admitted at opposite points so as to balance the pressure upon the piston, a couple of reciprocating piston-valves adapted to control the said ports, a rock-shaft provided with crank-arms having suitable connection with the stems or rods of said valves, and a handlever for rocking said shaft for the purpose of reversing the engine.

30. A compound reversible rotary engine, comprising the two cylinder-casings and pistons rotating therein; suitable abutments cooperating with said pistons, the casings being provided with suitable ports for admitting and exhausting steam to and from the pistonchambers, piston-valves adapted to control the said ports, a rock-shaft provided with crank-arms having suitable connection with the stems or rods of said valves, and means for rocking said shaft for the purpose of reversing the order of admission and exhaust and thereby reversing the engine.'

3l. In a reversible rotary engine, a casing providing a piston-chamber, a piston rotating concentrically within said piston-chamber and providedr with piston projections, rotary abutments arranged'at eitherside of the piston and provided with recesses adapted to receive the said-piston projections, a couple of valvechambers each provided with a port leading to and opening into the piston-chamber at a point immediately above the adjacent abutment, and each valve-chamber having a port leading to and opening into the piston-chamber at a-point immediately below the adjacent abutment; a two-disked piston-valve in each valve-chamber, a balancing port or duct for yconnecting the opposite ends of each valvechamber, a port or duct connecting one valvechamber withthe other valve-chamber, a port vor duct connecting the balancing port or duct of one valve-chamber with the balancing port or duct of the other valve-chamber, a supplypassage opening into the duct which serves to connect the two valve-chambers, an ex- IOO IIO

hanst-passage leading from the ductl which serves to connect the two balancing ports or ducts, and means for shifting the said valves for the purpose of reversing the engine.

32. YIn a compound reversible rotary engine comprising a plurality of piston-chambers, a reversing-valve chamber having its end portions connected by a duct or passage and provided with supply and exhaust ports; the said valve-chamber having a pair of ports or ducts leading to one piston-chamber, and having also a pair of ducts or ports leading to the next or adjacent piston-chamber; a threedisked reciprocating piston-valve inclosed in said valve-chamber and adapted to control the said ports, and means for shifting the said valve for the purpose of reversing the engine.

33. A compound double-expansion rotary engine, comprising high, intermediate and low pressure piston-chambers, pistons rotating concentrically Within said chambers and provided with piston projections, the piston projections in the high-pressure chamber alternating with those in the intermediate-pressure chamber, and the piston projections in the latter chamber alternating with those of the low-pressure chamber; rotary abutments provided with recesses adapted to receive the said piston projections, suitable supply and exhaust ports for admitting and exhausting steam to and from the said piston-chambers, the steam being admitted to each chamber at opposite points so as to balance the pressure upon the inclosed piston; and the steam being primarily admitted to the high-pressure chamber wherein it operates to rotate the inclosed piston without expanding, the exhaust from the high-pressure chamber being received and expanded within the intermediate-pressure chamber, and the exhaust from the latterbeing received and expanded within the low-pressure chamber.

34. A compound double-expansion rotary engine,comprising the high, intermediate and low pressure piston-chambers, pistons rotating concentrically therein and provided with piston projections, four of such projections in each chamber, the piston projections of the high-pressure chamber alternating with those of the intermediate-pressure chamber, and the piston projections of the latter alternating with those of the low-pressure chamber; rotary abutments arranged at either side ot' said pistons and provided with recesses adapted to receive the said piston projections, inlet and outlet ports adjacent to said abutments for admitting and exhausting steam to and from the said chambers, the steam being admitted at opposite points so as to balance the pressure upon the pistons; and the steam being primarily admitted to the high-pressure chamber wherein it operates to rotate the inclosed piston without expanding, the exhaust from the high-pressure chamber being received and expanded within the intermediatepressure chamber, and the exhaust from the latter being received and expanded Within the low-pressure chamber.

35. A compound double-expansion rotary engine, comprising two cylinder-casings, a cylindric piston rotating concentrically within each casing, each piston being provided with three flanges serving to divide the interior of each casing into two compartments, the two compartments in one casing serving as high and intermediate pressure chambers, and the compartments in the other chamber combining to serve as a' low-pressure chamber; rotary abutm ents arranged at either side of said pistons and provided with recesses adapted to receive the piston projections, the piston projections of the high-pressure cha1n= ber alternating with those of the intermediate-pressure chamber, and those of the latter alternating With those of the low-pressure chamber; three or more horseshoe-shaped rings loosely mounted upon each abutmentshaft opposite to the piston-anges, steam spaces or cavities back of the abutments and rings, pressure being maintained in such spaces or cavities by the steam carried in the abutment-recesses, and such pressure serving to balance the pressure upon the said abutments and rings and also to keep the former in contact with the pistons; the said casing being provided with suitable ports for' admitting and exhausting steam to and from the said piston-chambers, such admission being at opposite points so as to balance the pressure upon the pistons; the steam being primarily admitted to the high-pressure chamber wherein it operates to rotate the inclosed piston without expanding, the exhaust from the high-pressure chamber being received and expanded Within the intermediate-pressure chamber,- and the exhaust from the latter be'- ing received and expanded within the lowpressure chamber.

EDWARD C. WARREN.

Vitnesses:

EMILY NORTH MURPHY, JOHN E. OANNING.

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